Install duplicacy-cli with Homebrew Cask

Project links

• Homepage

Commands and aliases

• duplicacy

Project history

The public Duplicacy repository was created in 2016 by Gilbert Chen. Its README describes the repository as hosting source code, design documents, and binary releases for the command-line version, with a separate web GUI frontend available from duplicacy.com.

Duplicacy's technical identity is lock-free deduplication: chunks are saved independently by hash rather than through a centralized chunk database, allowing multiple computers to back up to the same cloud storage without communicating directly.

The README notes that the Duplicacy paper explaining the design was accepted by IEEE Transactions on Cloud Computing, which gives the project an unusual bridge between practical backup tooling and published distributed-storage research.

Adoption history

Duplicacy adoption grew around users who wanted encrypted, deduplicated backups to ordinary cloud storage with concurrent clients. GitHub metadata shows several thousand stars by 2026, and the Homebrew cask packages the prebuilt CLI binary rather than building from source.

The project ships native binaries through GitHub releases and supports many cloud backends, including local disk, SFTP, Dropbox, Amazon S3, Wasabi, Google Cloud Storage, Azure, Backblaze B2, Google Drive, OneDrive, OpenStack Swift, WebDAV-backed services, and others listed in the README.

How it is used

Users initialize repositories with Duplicacy metadata, store preferences under `.duplicacy/preferences`, and run commands such as backup, restore, check, prune, and copy against configured storage backends. Credentials may be kept in `.duplicacy/keyring` or referenced through preferences depending on backend and platform integration.

Duplicacy is commonly compared with restic, duplicity, Duplicati, Attic, and bup because all solve encrypted backup and retention problems with different repository formats and locking assumptions.

Why package nerds care

Duplicacy is package-nerd significant because it is a backup tool whose packaging is tied to licensing and binary distribution, not just source availability. The CLI is source-visible and free for personal use, while non-trial commercial backup use requires licenses under upstream terms.

Its design also stresses package-manager thinking about backup tools: small CLI binary, many remote backends, local metadata directories, keyring integration, and a repository format that users expect to survive across upgrades.

Timeline

• 2016: The public Duplicacy GitHub repository is created.
• 2020: The lock-free deduplication paper is accepted by IEEE Transactions on Cloud Computing according to the README.
• 2023: Duplicacy CLI 3.2.x releases are published.
• 2025: Duplicacy CLI 3.2.5 is published and packaged by the Homebrew cask metadata for this batch.

Related projects

• Vertical Backup is a related product named by the README as a Duplicacy-based edition for VMware vSphere.
• duplicity, bup, Duplicati, Attic, and restic are related backup tools discussed directly in Duplicacy's comparison section.
• The Duplicacy Web GUI is related as the official graphical frontend for Windows, macOS, and Linux.

Sources

• https://raw.githubusercontent.com/gilbertchen/duplicacy/master/README.md documents lock-free deduplication, the IEEE paper, CLI/Web GUI split, supported storage backends, comparisons, and license terms.
• https://github.com/gilbertchen/duplicacy/blob/master/GUIDE.md documents command-line usage.
• https://api.github.com/repos/gilbertchen/duplicacy documents repository creation, language, stars, license metadata, and activity.
• https://api.github.com/repos/gilbertchen/duplicacy/releases documents CLI release history.